1. Field of the Invention
The invention relates to a difunctional weather-resistant stabilizer, more particularly to a difunctional weather-resistant stabilizer having one terminal semicarbazide functional moiety and one terminal hindered phenol functional moiety.
2. Description of the Related Art
Common organic polymer materials, for example, plastics, resins, cosmetics, pigments, paints, and textiles, are liable to be damaged due to the influence of light, heat, acid, base, or nitrogen oxide (NOx) to result in discoloration or material decomposition. If a suitable organic additive such as an antioxidant or a photostabilizer is added to the organic polymer material, the organic polymer material may be protected from damage. For instance, adding chemical substances that have an antioxidant capability or a UV light absorbing characteristic to absorb or convert UV light energy can help maintaining the luster and durability of the material.
Current industries increase the antioxidant capability of organic polymer materials by adding additives such as a hindered phenolic antioxidant or a phosphorus-containing organic antioxidant. Both US 2013/0225734 A1 and US 2012/0252931 A1 disclose a hindered phenolic antioxidant which is used to increase antioxidant capability. Although the antioxidant capability of organic polymer materials in a heating or baking process may be enhanced by adding the hindered phenolic antioxidant, yellowing resistance (NOx resistance) and alkali resistance of the organic polymer material are significantly insufficient.
It is reported by Shevchenko, V. V. et al. (Zhurnal Organicheskoi Khimii (1982), 18 (12), 2547-9 (USSR)) that a compound having 1,1-dimethylhydrazine functional moieties on its two terminals is obtained by reacting 1,1-dimethylhydrazine with hexamethylene diisocyanate or by reacting 1,1-dimethylhydrazine with (methylene biphenyl)diisocyanate.